Storage tank



Sept. 24, 1946. A. STARRET STORAGE TANK 5 Sheets-Sheet 1 Filed Oct. 16,1941 Sept. 24,1946 H. A. STARRET 23 3 STORAGE TANK Filed Oct. .16, 1941S SheetS-Sheet 2 kj-louJardfl. Skafreb 5 Sheets-Sheet 3 awe/M300 Sept.24, 1946. H. A.- STARRET 0 7 Filed Oct. 16, 1941 5-Sheets-Sheet 4 wwwiPatented Sept. 24. 1946 STORAGE TANK Howard A. Starr-ct, United StatesArmy 7 Application October 1.6,, 1941, Serial No. 415,229

(01. 220-18) 7 .(Grmtlad under the act of 'March a, 1883, as

3 Claims.

The invention described herein, if patented, may be manufactured andused. by or for the Government for governmental purposes without thepayment of any royalty thereon.

'I'hisinvention relates toimprovements in tan especially adapted for thestorage of. gasoline in bulk.

In; time of war and during periods when a countryis constantly subjectedto bombing attacks and the like, it is essential that means be provided.for the safe storage of' gasoline and other highly inflammablesubstances.

Therefore, it is an object of this invention-to provide a storage tankof novel construction Which can be quickly and easily assembled, andinstalled at various locations for :the storage of gasoline in bulk.

Another object of the inventionis. to build the tank in sections so thatit can be assembled at any place it is desired to locate the tank.

Therefore, by constructing the tank in sections, it is possible to buildtanks of any desired length or width by removing or adding sections, thesame design being applicable to either large or small tanks. The size ofthe plates forming these sec- Y support the tanks on a bed plate 'sothat the 1 tanks can withstand horizontal earth vibrations. A furtherobject of. this invention is the pro vision of a storage tank sodesigned and constructed that it can be adequately inspected with aminimum amount of danger to life and property, minimize the problem ofweathering and provide for the maintenance of the tank by a greatlyreduced staff.

These and other objects are attained by the novel constructionhereinafter described in the following specification and pointed out inthe accompanying drawings forming a part hereof, and in which: I

Fig. l is a perspective view of a quarry showing the tanks Within. i g rFig. 2 is a perspective view of a portion. of the tanks inthe interiorof the quarry. 1 V

Fig. '31 is a perspective view of the'interior of a speciallyconstructed building to; house the tanks.- 7

Fig. 4 is a; perspective view of a portion ofthe tanks in the interiorof'the building shown'in Fi 3.,

Fig. 5 is a top plan view of a tank embodying the invention.

amended April 30, 1928, 370 O. G. 757) Fig. 6 is, asectional elevationalview taken longitudinally of the tank along the intersection of theintermediate cylindrical portions and along the intersection of the endhemispheres.

Fig. '7 is a sectional view taken transversely of the tank at one of thetransverse frame members.

Figure8 is a fragmentary view of the invention, showing the external legof the compression member of one truss member 29, and its foot piece.

Referring to the drawings, and more particularly to Figs. 1 and -2,there are shown the tanks 10 located in an existing quarry or cave II.The storage tanks I0 will be seen to have thegeneral shape oftwointersecting cylinders, with the ends assuming .the shape of twointersecting hemispheres. The end sections are identical in construction,and the cylindrical portions of the tank are formed from a pluralityvof sections of identical construction. which enable the formation oftanks of any; desired size by adding intermediate cylindrical sections.a 5 The quarry is equipped with a water line l2 for fire protection anda vapor vent pipe I3 is used to vent all vapors from the tanks- Thestorage tanks areeequipped with the usual pipe lines 14 which arecontrolled by conventional valves l5 and. conventional pressure gauges16 areplaced in an accessible position on the tank. Ladders I! areprovided to gain access to the gauges I6, and a. drainage system I8 isprovided for the tanks. A blower ventilating system I9 is provided toexhaust all fumes and thoroughly ventilate the interior of the quarry.

' Figs. 3.and 4. are identical with Figs. land 2 except that a speciallyconstructed building 20 has been erected to hold the-storage tanks Ill.Drains 2| have been provided to clean the tanks when necessary and thesetanks as shown possess all the elements previously referred to and inaddition there are also shown stairs 22 by which access is gained to theoutside, since, as shown, the building is built underground.

. In Figure 6v there is shownthe intersection of the two hemispheresforming one end section of the tank, and theintersection at theintermediate cylindrical portions of the tank. At the intersection oftheend hemispheres there is an end fram 'comprising anarcuate beam 23,braced. by a vertical post 24 and angular plates 25. The beam 23terminates in straight horizontal inwardly extending horizontal portions23' attop and bottom, which are parallel toone another andcoincidentwith the line of intersection of the two cylindrical portions of thetank. The

ends of the portions 23 of the end frame abut, as at 28, short beams orrails 26 at top and bottom of the tank. The rails as shown in Figure 6have two vertical strut members 21 extending therebetween and securedthereto, one of the struts being at the right hand extremities of thetwo rails 26, while the other of the two struts is located and securedmidway of the horizontal extent of the rails 26. The members 26 may abutsimilar rails 26 next adjacent longitudinally, as seen in Figure 6.

In Figure 7 there are shown truss members or frames 29, each of whichcomprises an arcuate beam 30, extending over an arc of approximately 220degrees subtending a vertical chord, a vertical post or compressionmember 3!, spaced oppositely from the center of the are from the chord.mentioned, connected at its upper extremity to the beam 30 and connectedat a lower part of the beam 30 so as to subtend an arc of approximately105 degrees in this particular instance, also a lattice of horizontalbars 32 and diagonal braces 33 connected between the arcuate beam and.the post 3|. It will be noted that the arrangement of these bars andbraces is such as to transmit any weight load on the beam 30 to the post3|. The inner ends of the beam 30 extend some distance to theirextremities without bracing or support other than their inherentresistance to bending. The truss members 29 of Figure 7 are disposed inmutual opposed relation in a common plane which is normal to the axes ofthe two cylindrical portions of the tank, as indicated throughout thelength of the tank in Figure 5. They thus abut the interposed parts 23'or 26, according to the location of the members 29 longitudinally in thewhole frame of the tank, and together each two opposed and abuttingmembers 29 constitute virtually a unitary cross frame. In addition totheir use as transverse members, similar truss members 2911 and 2912 arealso used in the end hemispheres, differing from the first in that theirarcuate beams extend over an arc of only 180 degrees, but with theirpost members 3| subtending the same are on the curved beam as in Figure7, this also being indicated in Figure 5.

Each hemisphere has twosuch frame members of limited arc, one designated29a, Figure 5, arallel to and near the arcuate beam 23 which joins thetwo hemispheres; the other, designated 29b is disposed between. and atan angle of fortyfive degrees to, the member 29a and a next adjacenttransverse truss member 29 which is included in the hemisphere. Themembers 29a and 291; have the extremities of their arcuate beams 30 inabutment with the side of the transverse member 29, at a vertical chordwhich intersects the axis of the respective cylindrical part which isalined therewith. In this way the hemispherical part built over theseend frames and extending to the curved beam 23 forms a symmetricalcontinuation of the wall of the cylindrical part as in Figure 5, and thetwo hemispheres intersect with a horizontal section the external contourof which corresponds to the contour of the upper and lower parts invertical section as seen in Figure 7. Thus there is no break orvariation of the direction or unit of stress on the metal sheath or skinof welded sheets forming the exterior of the tank.

It may be noted from Figures and '7 that a boundary defining thesuperficial area beneath the tank, and drawn across the outer ends ofthe tank foot plates'36, greatly exceeds in width the vertical dimensionof the tank, and from Figure 8 it may be seen that preparation forsupport of the tank consists in simply levelling the ground area uponwhich these foot plates are to be set. In consequence of the relation ofthe bounds of the supports and the height of the tank, it will beappreciated that it will be highly resistant to tilting by lateralforces which would tend to upset tanks of greater proportionate height,and with the simple surface bearing of the broad foot plates 36, thatabrupt and rapid translative movements of the ground beneath the feetwill tend Y to result in relative movement of the ground withoutmovement of the foot plates equally, with a consequent minimizing ofracking strains in the tank supports and framing. It is known that theshock wave of an earthquake moves at a speed of several hundred feet persecond, and that earth shock waves from detonated nearby explosives havea rate several times as great, the effect of which varies according tothe distance from the point of explosion and the amount and nature ofthe explosive.

After the shock wave, there is a following translative earth movementpartaking of the nature of a wave and of greater linear movement in thedirection of its progress, but of lesser speed than the first shockwave, although still so rapid for large bombs that before inertia of thetank and content can be overcome the ground will as a mass moverelatively under the foot plate, thus reducing the stresses produced inthe tank as compared to one fixed with a footing embedded in the ground.By way of illustration of the effects to be overcome, it may beexplained that research has shown that explosion of a bomb containing1000 pounds of TNT will produce a translative movement horizontally oftwo or more inches at a distance of fifty feet from the point ofdetonation, this movement having a particle rate of approximatelysixtyfeet per second, at the distance named.

No special foundation is necessary as each vertical post 3| rests on abase plate 36, Fig. 7,

being secured thereto by a short horizontal angle piece 35. A web plate34 is also secured to some or all of the parts 3| 36, 35. The upper edgeof vertical plate 34 is arcuate to conform to the circular shape of thearcuate beam 30 and is secured thereto by short arcuate angle piece 38.The inclined edge of web plate 34 may be reinforced by an inclined anglepiece 31.

It is clear that by making the structure of the trusses for theintermediate sections and the end sections identical, interchangeabilityis provided and the various elements can ebe formed in shops remote fromthe final location of the tank. It will appear, therefore, that theassembly of the truss frame at the location of the tank would be arelatively simple procedure. The various elements of the frame arejoined by welding or the like and after construction the frame can becovered by the metal sectional sheets welded to each other to provide awater-tight tank.

A number of tanks may be constructed near each other and require only asmall number of attendantsfor maintenance. When a suitable location isfound after preliminary surveys have been made, the trusses and othermembers of the frames can be shipped to the location for assembly. Itshould be appreciated that the only survey required is to ascertain thatthe necessary width and height of chamber space is available, and thatthe floor may be levelled to receive the foot plates 36 at properintervals. The tanks may be constructed any length by addingintermediate truss frames 29 and the interposed strut and bar sections26-41 as required, the end sections being the same regardless of thelength of the tank. The tank is in that way accommodated to the spaceavailable as it is erected, without detailed plans or exact instrumentalsurveys. In the course of the work of erection, eachtruss frame 29 maybe set in place on its foot plate upon the levelled floor surface and asthe inner end of the foot plate is inwardly of the center of gravity ofthe frame piece, it will remain erect while the parts 2621, and anopposed member 29 are brought into place. These three units may beunited as they are thus positioned, or left in simple abutment until thewelding of the sheet metal covering or skin. The scarf form of the endsof the rails 26 and beam parts 23' shown at 28 in Figure 6, will causepro-per support of the pieces in proper alinement until uniting of theassembled parts. The tank can be easily and economically repaired andpainted because of its accessibility.

From the above description it can be seen that there has been provided asimple andefiective tank structure for housing gasoline.

The foregoing description is to be regarded as descriptive only and notlimitative of the invention of which obviously embodiments may beconstructed without departing from the scope of the appended claims.

Having thus described the invention, What is claimed as new and desiredto secure by Letters out the cylindrical and spherical parts, each ofsaid frames including identical circular truss parts abutting andconforming to the circular form of the said wall skin in a plane normalto the abutted wall skin parts, said truss parts intermediately of saidends being opposed in pairs abutting at upper and lower intersections oftheir circular parts at a vertical chord coincident with theintersections of said cylinders, each said truss part including avertical compression memberspaced outwardly of said chord and havingsupporting relation to the upper and lower parts of each said circulartruss part and respective adjacent wall skin parts, each said verticalcompression member having an external lower leg continuation fixedrigidly with the respective truss part and braced to prevent horizontaldisplacement of the leg relative to the tank, each said external legcontinuation having a foot plate adapted to rest and slide on ahorizontal bed and positioned to support the tank clear of subjacentearth, whereby the tank may be set up and maintained free of damage byshock Waves and abrupt horizontal displacements of earth under and inrelation to any of said foot plates.

' framing for a tank for storage of pressure fluids,

adapted to be assembled to various capacities, comprising a multiplicityof identical vertical planiform sector-shaped truss members, all saidmembers arranged in horizontally spaced relation to lie within andsymmetrically conform at their arcs with the surfaces of twogeometrically projected parallel horizontal axially spaced intersectingcylinders at a common level and with hemispherical intersecting endsconcentric with and of the same radius as said cylinders, the said trussmembers inwardly of those in the said hemispherical ends being arrangedin opposed pairs, their circular parts meeting at a vertical chordalplane coincident with the intersections of said cylinders whereby eachsaid pair constitutes a respective transverse frame normal to the axesof said cylinders, each said truss member comprising an external curvedbeam defining a circular arc boundary of the member, and including avertical compression member joined to upper and lower parts of saidcurved beam and spaced outwardly of the center of its said arc, avertical strut in said chordal plane at each frame extending between theupper and lower said meeting parts of the opposed truss members, eachend of said framing including an end frame having a semicircular partcoincident with the intersection of said hemispherical intersecting endsand continued at top and bottom a distance as rectilinear horizontalparallel members extending across the plane of at least the next of saidtransverse frames, joined to at least one said vertical strut andterminating thereadjacent, upper and lower horizontal short rail membersacross and attached to one or more of said struts and between adjacentopposed truss members, aligned with and arranged to abut respective saidhorizontal continuations of the said end frames and to abut the ends ofsimilar adjacent rail members, said truss members each having anexterior downward leg continuation of its said vertical compressionmember formed with a respective broad horizontal planiformground-engaging foot plate for support of the tank, adapted to restslidably upon aground surface, whereby said truss members will standerect in the assembled relation described, and whereby a continuous wallskin of sheet metal plates may be applied thereto and welded to eachother and to said framing to hold said framing in assembly and to opposepressures of fluids in the tank by inherent tensional strength of thewall skin and to define externally a form corresponding to that of saidgeometrically projected intersecting cylinders and hemispherical ends.

3. The structure of claim 2, in which a load I transmitting truss workis included between the said curved beam and said compression memberprincipally at the outer side of the latter, said beam being extended ateach of its ends a substantial distance without trussing, each said footplate extending inwardly beyond a vertical from the center of gravity ofthe truss member.

HOWARD A. STARRET.

